{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:05:09Z","timestamp":1760241909076,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,10,10]],"date-time":"2018-10-10T00:00:00Z","timestamp":1539129600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["No.2016R1D1A1B03934812"],"award-info":[{"award-number":["No.2016R1D1A1B03934812"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fingerprint is a typical indoor-positioning algorithm, which measures the strength of wireless signals and creates a radio map. Using this radio map, the position is estimated through comparisons with the received signal strength measured in real-time. The radio map has a direct effect on the positioning performance; therefore, it should be designed accurately and managed efficiently, according to the type of wireless signal, amount of space, and wireless-signal density. This paper proposes a real-time recursive radio map creation algorithm that combines Wi-Fi and geomagnetism. The proposed method automatically recreates the radio map using geomagnetic radio-map dual processing (GRDP), which reduces the time required to create it. It also reduces the size of the radio map by actively optimizing its dimensions using an entropy-based minimum description length principle (MDLP) method. Experimental results in an actual building show that the proposed system exhibits similar map creation time as a system using a Wi-Fi\u2013based radio map. Geomagnetic radio maps exhibiting over 80% positioning accuracy were created, and the dimensions of the radio map that combined the two signals were found to be reduced by 23.81%, compared to the initially prepared radio map. The dimensions vary according to the wireless signal state, and are automatically reduced in different environments.<\/jats:p>","DOI":"10.3390\/s18103390","type":"journal-article","created":{"date-parts":[[2018,10,10]],"date-time":"2018-10-10T11:53:13Z","timestamp":1539172393000},"page":"3390","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Real-Time Recursive Fingerprint Radio Map Creation Algorithm Combining Wi-Fi and Geomagnetism"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8198-0439","authenticated-orcid":false,"given":"Ju-Hyeon","family":"Seong","sequence":"first","affiliation":[{"name":"Department of Electrical and Electronics Engineering, Korea Maritime and Ocean University, #727 Taejong-Ro, Youngdo-Gu, Busan 49112, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong-Hoan","family":"Seo","sequence":"additional","affiliation":[{"name":"Division of Electronics and Electrical Information Engineering, Korea Maritime and Ocean University, #727 Taejong-Ro, Youngdo-Gu, Busan 49112, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,10,10]]},"reference":[{"doi-asserted-by":"crossref","unstructured":"Li, W., Wei, D., Lai, Q., Li, X., and Yuan, H. 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